MXPA96002933A - Positive electrode recharge - Google Patents

Abstract

The present invention relates to methods for manufacturing solid state composite electrodes based on active sulfur. The method starts with a step or step of combining the electrode components (including an electrochemically active material, an electronic conductor and an ion conductor) in a mixture. The mixture is then homogenized so that the electrode components are well mixed and free of agglomerate. Immediately afterwards, before the components of the electrode settle or separate in some important grades, the mixture is deposited on a substrate to form a thin film. Finally, the deposited film is dried to form the electrode so that the components of the electrode do not redistribute in an important way.

Description

RECHARGEABLE POSITIVE ELECTRODE 1 DESCRIPTION BACKGROUND AND FIELD OF THE INVENTION This invention relates generally to positive electrodes characterized by active sulfur. The electrodes are preferably rechargeable, and in some preferred embodiments are constructed in a thin film 0 presentation. Various negative electrodes, such as alkali metals, alkaline earth metals, transition metals, and carbon insertion electrodes, among others, ^ ^ can be coupled with positive electrodes, to provide battery cells, preferably having high specific energy (Wh / kg) and high energy density (Wh / 1). The rapid proliferation of portable electronic devices in the international market has led to a corresponding increase in the demand for advanced secondary batteries. The rriiniaturization of such devices as, for example, cell phones, laptops, etc., has naturally propitiated the desire for rechargeable batteries that have high specific energies (low weight). At the same time, the staging of interests with respect to the environmental impact of waste technologies has led to a perceptible change away from primary batteries and towards rechargeable systems. In addition, the increase in awareness regarding toxic waste has led, in part, efforts to replace toxic cadmium electrodes in nickel / cadmium batteries with the most benign hydrogen storage electrodes 5 in nickel cells. metal hydride. For the above reasons, there is a large potential market for benign secondary battery technologies with respect to the environment.

Secondary batteries are widely used in modern society, - • particularly in applications where large amounts of energy are not required.

However, it is desirable to use batteries in applications that require considerable power, and many efforts have been expended to develop appropriate batteries for high specific energy, medium power applications, such as, for electric vehicles and load equalization. Of course, such batteries are also suitable for use in less powerful applications such as cameras or portable recording devices. At this time, most of the most common secondary batteries are probably the acid batteries used in automobiles. Those batteries have the ^^ advantage of being able to operate for many load cycles without significant loss of * functioning. However, such batteries have a low energy to weight ratio.

Similar limitations are found in most other systems, such as Ni-Cd and nickel / metal hydride systems. 5 Among the factors that lead to the successful development of high energy specific batteries, is the fundamental need for high cell voltage and low weight equivalent electrode materials. The electrode materials must also meet the basic electrochemical requirements of sufficient electronic conductivity and the oxidation-reduction reaction, as well as chemistry within the temperature range for a particular application. Preferably, the electrode materials must be reasonably cheap, widely available, non-toxic, and easy to process. Thus, a small, lighter, non-toxic and cheaper battery is sought for the next generation of batteries. The low lithium equivalent weight makes it attractive as a battery component electrode to improve weight ratios, lithium also provides more energy by volume than traditional nickel and cadmium standard batteries do.

The low equivalent weight and low cost of sulfur and its non-toxicity makes it - ^ also an attractive candidate as a drum component. Successful organosulfur / cell lithium batteries are known. (See, De Jonghe et al., U.S. Patent Nos. 4,833,048 and 4,917,974; and Visco et al., U.S. Pat. No. 5,162,175.) 5 However, employing a positive electrode based on elemental sulfur in an alkaline-sulfur metal battery system has been considered problematic. Although theoretically the reduction of sulfur to an alkali metal sulfide confers a large specific energy, it is known that sulfur is an optimal insulator, and problems have been noticed when using it as an electrode. Such problems referred by the experts in the art include the need to bind the sulfur to an inert electronic conductor, very low percentages of utilization of the volume of material, poor reversibility, and the formation of an insulating layer of sulfur on the particles of sulfur. carbon and the surface of the current collector that electronically isolates the rest of the components of the electrode. (DeGott, P., "Polymere Carbone Soufre Synthese et Propriétes 5 Electrochimiques," doctoral thesis at the Institut National Polytechnique de Grenoble (thesis defense date: June 19, 1986) on page 117.) Similarly, Rauh et al., "A Lithium / Dissolved Sulfur Battery with an Organic Electrolyte, "J. Electrochem, Soc. 126 (4): 523 (April 1979) state on page 523: "Both the S8 and its final discharge product, Li2S, are electrical insulators, 0 * ß yes, it is likely that this isolation of the positive electrode material ... leads to the poor results of the Li / S cells." In addition, Peramunage and Licht, "A Solid Sulfur Cathode for Aqueous Batteries," Science, 261: 1029 (August 20, 1993) state on page 1030: "At low temperatures (environment), elemental sulfur is a highly insoluble insulating solid, 5 and it is not expected to be a useful positive electrode material. " However, Peramunage and Licht found that interencarando this sulfur with an aqueous solution of polysulfide saturated with sulfur converts it from an insulator to an ionic conductor.

The use of sulfur and / or polysulfide electrodes in lithium batteries is known Aqueous or aqueous droplets of liquid electrolyte (ie in liquid presentations). For example, Peled and Yamin, U.S. Patent No. 4,410,609, describe the use of a Li2Sx polysulfide positive electrode made by the direct reaction of Li and S in the tetrahydrofuran (THF). Typically, poor cyclization efficiency in such a cell occurs due to the use of a liquid electrolyte with lithium metal foil, and the Peled and Yamin patent describes the system for primary batteries. Rauh et al., "Rechargeable Lithium-Sulfur Battery (Extended Abstract), J. Power Sources, 26: 269 (1989) also notes the poor cycling efficiency of such cells and states on page 270 that 0"most of the cells failed as a result of depletion of lithium. " references to lithium-sulfur battery systems in liquid presentations ^^ include the following: Yamin et al, "Lithium Sulfur Battery," J. Electrochem. Soc, 135 (5): 1045 (May 1988); Yamin and Peled, "Electrochemistry of a Nonaqueous Lithium / Sulfur Cell, "J. Power Sources, 9: 281 (1983); Peled et al.," Lithium-Sulfur 5 Battery: Evaluation of Dioxolane-Based-Electrolytes, "J. Electrochem. Soc, 136 (6): 1621 (June 1989); Bennett et al., U.S. Patent No. 4,469,761; Farrington and Roth, U.S.

Patent No. 3,953,231; Nole and Moss, U.S. Patent No. 3,532,543; Lauck, H., U.S. Patent Nos. 3,915,743 and 3,907,591; Societe des Accumulateurs Fixes et de Traction, "Lithium-sulfur battery," Chem. Abstracts, 66: Abstract No. 11 1055d on page 10360 0 ^^ 1967); and Lauck, H. "Electric storage battery with negative lithium electrode and positive sulfur electrode," Chem. Abstracts. 80: Abstract No. 9855 on pages 466-467 (1974).) DeGott, supra, notes on page 118 that alkaline-sulfur metal battery systems have been studied in different presentations, and then presents the 5 problems with each of the presentations studied. For example, he notes that an "all liquid" system had been abandoned quickly due to a variety of reasons including, among others, the corrosive problems of sulfur and liquid lithium, the dissolution of lithium in the electrolyte causing the system to self-discharge, and that the lithium sulphide that forms in the positive (electrode) reacts with the sulfur to give Li2Sx polysulfides that are soluble in the electrolyte. With respect to the alkali-sulfur metal systems where the electrodes are melted or dissolved, and the electrolyte is solid, whose function in temperature ranges specimens from 130 ° C to 180 ° C and from 300 ° C to 350 ° C, DeGott states on page 118 that such batteries have problems, such as, progressive diminution of the capacity of the cell, appearance of electronic conductivity in the electrolyte, and safety and corrosion problems. DeGott then lists problems encountered with alkaline-sulfur metal battery systems where the electrodes are solid and the electrolyte is 0 an organic liquid, and by extension where the negative electrode is solid, the ^^ electrolyte is solid, and the positive electrode is liquid. Such problems include 1 incomplete sulfur reduction, mediocre reversibility, weak maximum specific power (limited operation at low discharge rates), destruction of the Li2S passivating layer as a result of its reaction with dissolved sulfur leading to the formation of soluble polysulfides, and with the stability of the solvent in the presence of lithium. DeGott also describes on page 117 a fundamental barrier to good reversibility due to the following. Because the alkali metal sulphides are ionic conductors, they allow, to the extent that a current collector is 0 ^ K "adjacent to sulfur, the propagation of a reduction reaction. In contrast, its reoxidation leads to the formation of an insulating layer of sulfur in the positive electrode that ionically isolates the rest of the compound, resulting in poor reversibility. DeGott concludes on page 119 that it is clear that whatever the presentation adopted by an alkali-sulfur metal battery system the insulating character of sulfur is a major obstacle difficult to overcome. He then describes preliminary electrochemical experiments with a sulfur-containing electrode prepared from a mixture. The mixture was prepared by mixing the following components in acetonitrile: 46% sulfur; 16% acetylene black; and 38% of thiope) 8 / LiC104 (polyethylene oxide / lithium perchlorate). The resulting mixture was then deposited on a stainless steel substrate by "capillary action." From those preliminary experiments, DeGott concludes on page 128 that it is clear that, even when the efficiency of the composite electrode is optimized (ie, by multiplying the triple point contacts) that elemental sulfur can not be considered to constitute an electrode for a battery secondary, in a presentation or "all solid" format. Current solid-state lithium secondary battery systems are limited to 0 a specific energy of approximately 120 Wh / kg. It would be highly desirable to have ^^ a battery system characterized by higher specific energy values. It would be even more desirable if solid state batteries having practical practical energy values greater than about 150 Wh / kg could operate at room temperature. It would be of further advantage if the solid state batteries having high specific energy and operating at room temperature could be safely manufactured into units with reproducible operating values. In lithium cells where a liquid electrolyte is used, the loss of the electrolyte may allow the exposure of lithium to the air, where it reacts rapidly with water vapor. A substantive coating can prevent such and protect users and the environment from exposure to hazardous, corrosive, combustible or toxic solvents but add undesirable weight to the battery. A solid-state battery would greatly reduce such problems of electrolyte loss and lithium exposure, and would reduce the weight of the battery. In addition, a battery formula that overcomes the lithium depletion problem 5 described in the prior art, for example, Rauh et al., Supra. It would have many advantages. In summary, the disadvantages in current metal-sulfur battery systems available include poor cycling efficiency, poor reversibility, lithium depletion, or operating temperatures above 200 ° C, among other problems. The Professionals in the art of battery have long sought a battery system "solid-state sulfur-solid state or gel that could overcome these limitations.

BRIEF DESCRIPTION OF THE INVENTION This invention provides a positive electrode for a battery cell having low equivalent weight and high cell voltage and consequently high specific energy, and operates over a wide temperature range including ambient and subambient temperatures. An exemplary operating temperature range for the 0 batteries of this invention is from -40 ° C to 145 ° C. The batteries of this invention Thin-film type battery cells are The positive electrode of this invention comprises a sulfur-based active material having a relatively low equivalent weight. The electrode is a compound 5 comprising, in the theoretical state of total charge, elemental sulfur, preferably an ionically conductive material, and an electronically conductive material. In the discharge, the active sulfur of the positive electrode reacts with the metal of the negative electrode, and form sulphides and polysulfides of metal. For example, where M is the metal of the negative electrode, the total cell reaction can be described as indicated below: x / zM + S = M? / ZS wherein M is any metal that can function as an active component in a negative electrode in a battery cell wherein the active sulfur is the active component of the positive electrode; x = 0 to x = 2; z = the valence of the metal; and S is sulfur.

M is preferably selected from the group consisting of alkali metals, alkaline earth metals, and transition metals, M is more preferably selected from the group consisting of the alkali metals, and still more preferably lithium or sodium, M is more preferably lithium. More specifically, for example in a preferred embodiment of this invention where the negative electrode contains lithium, the total cell reaction where z = 1 can be described as follows: xLi + S - LixS, 0 When, x = 2, 100% of the theoretical specific energy has been released from the ^^ system. At discharge, the positive electrode is transformed into a combination of sulfur, polysulfides and metal sulphides, and during the discharge process the 5 proportions of the sulfur-containing components will change according to the state of charge. The charge / discharge process in the positive electrode is reversible. Similarly, when recharging, the percentages of the sulfur-containing ingredient will vary during the process. positive electrode is thus made from a composition of 0j ^? Lectrode comprising active sulfur, an electronically conductive material interspersed with active sulfur so as to allow electrons to move between the active sulfur and the electronically conductive material, and an ionically conductive material interspersed with the active sulfur so that allow the ions to move between the ionically conductive material and the sulfur. The ionically conductive material of the composite positive electrode is preferably a polymer electrolyte, more preferably a polyalkylene oxide, and furthermore, preferably polyethylene oxide in an appropriate salt which can be added. Additional ionic conductive materials for use in the positive electrode include the components described below in the solid state separator and gel state separator. Electronically conductive materials of the composite positive electrode include carbon black, electronically conductive compounds with carbon-carbon 5 conjugate and / or carbon-nitrogen double bond, for example but not limited to, electronically conductive polymers, such as, polyaniline, polythiophene, polyacetylene , polypyrrole, and combinations of these electronically conductive materials. The electronically conductive materials of the positive electrode may also have electrocatalytic activity. 0 The positive compound electrode based on sulfur can also optionally ^^^ comprising additives that improve performance, such as binders; electrocatalysts, for example, phthalocyanines, metallocenes, bright yellow (Reg.

No. 3051-11-4 of the Aldrich Catalog Handbook of Fine Chemicals; Aldrich Chemical Company, Inc., 1001 West St. Paul Avenue, Milwaukee, Wl 53233 (USA)) among 5 other electrocatalysts; surfactants; dispersants (for example, to improve the homogeneity of the electrode ingredients); and additives to form a protective layer (for example, to protect a negative lithium electrode), such as, organosulfur compounds, phosphates, iodides, iodine, metal sulfides, nitrides, and fluorides, Active in such electrodes in the theoretical state of total charge is 20% to 80% by weight. The active sulfur-based composite electrode is preferably processed so that the component particles are homogeneously distributed, and the segregation and / or agglomeration of the component particles is prevented. A metal-sulfur battery system constructed with the active positive sulfur-based composite electrode of this invention should have availability of at least 5%, and more preferably at least 10%, of the active sulfur. This availability corresponds to a minimum of 168 mAh per gram of sulfur included in the positive electrode. This is based on the theoretical value of 1675 mAh / g of sulfur at - * 100% availability. The electrolyte separator used in combination with the positive electrodes of this invention functions as a separator for the electrodes and as a means of transport for metal ions. Any electronically insulating and ionically conductive material that is electrochemically stable can be used. For example, it has been shown that polymeric, glass and / or ceramic materials are suitable as electrolyte separators, as well as other materials known to those skilled in the art, such as, compounds and membranes or porous materials of such materials. Preferably, however, the electrolyte solid state separator j * is any suitable ceramic, glass, or polymer electrolyte such as polyethers, polyimines, polythioethers, polyphosphazenes, polymer blends, and the like, in which a suitable electrolyte salt. In the solid state, the electrolyte separator may contain an aprotic organic liquid in which the liquid constitutes less than 20% (weight percent) of the total weight of the electrolyte separator. In the gel state, the electrolyte separator contains at least 20% (weight percent) of an aprotic organic liquid wherein the liquid is immobilized by inclusion of a gelling agent. Any eluting agent may be used, for example, polyacrylonitrile, PVDF or PEO. The liquid electrolyte for liquid pressentation batteries using the positive electrode of this invention is also preferably an aprotic organic liquid. The liquid presentation battery cells constructed using the positive electrodes of this invention would preferably further comprise a separator that would act as an inert physical barrier within the liquid electrolyte. Examples of such a separator include glass, plastic, polymeric materials, ceramics, and porous membranes thereof among other separators known to those in the art.

The positive solid state and gel state electrodes of this invention -j can be used in solid or liquid presentation batteries, depending on the specific presentation of the electrolyte separator and the negative electrode. Without considering the presentation of the batteries that use the positive electrode of this In the invention, the negative electrode can comprise any metal, any mixture of metals, carbon material or carbon metal capable of functioning as a negative electrode in combination with the active positive sulfur-based compound electrode of this invention. Accordingly, negative electrodes comprising any of the alkali metals or alkaline earth metals or transition metals for example, (the polyether electrolytes are known to carry divalent ions such ^ as Zn ++) in combination with the positive electrode of this invention are within the scope of the invention, and particularly alloys containing lithium and / or sodium. Preferred materials for negative electrodes include Na, Li and mixtures of Na or Li with one or more additional alkali metals and / or alkaline earth metals. The surface of such negative electrodes can be modified to include a protective layer, such as that produced in the negative electrode by the action of additives, including organosulfur compounds, phosphates, iodides, nitrides, and fluorides, and / or an inert physical conductive barrier. for metal ions - from the negative electrode, for example, transport of lithium ions in phosphate of 0 '^ ntio, or glasses of silicates, or a combination of both. Also preferred materials for negative electrodes include carbon, carbon inserted with lithium or sodium, and mixtures of carbon with lithium or sodium. Here, the negative electrode is preferably carbon, the carbon inserted with lithium or sodium, and / or a mixture of carbon with lithium or sodium. When the negative electrode is 5 carbon, the positive electrode is in a fully discharged state, comprising lithium or polysulfides and sodium sulfides. Particularly preferred negative electrodes for batteries are lithium inserted into highly disordered carbons, such as carbon-based poly p-phenylene, graphite intercalation compounds, and LiyC6 where y = 0.3 to 2, for example, LiC6, Li2C6 and LiC12. When the adhesive electrode -t is carbon, the cells are preferably assembled with the positive electrode in the fully discharged state comprising sodium or lithium sulphides and / or polysulfides. The use of negative carbon, carbon inserted with lithium or sodium electrodes, and mixtures of carbon with lithium or sodium with the positive solid-state and gel-state electrodes of this invention are especially advantageous when the battery is in liquid presentation. In another aspect, the current invention provides methods for forming an electrode containing active sulfur. Such methods may be characterized by including the following steps (a) combining active sulfur, an electronic conductor, and a conductor and ionic to form a mixture: (b) homogenizing the mixture to form a homogeneous mixture; and (c) forming the electrode containing active sulfur from the homogeneous mixture. The method is conducted in such a manner that the resulting electrode containing active sulfur has at least about 5% (and more preferably at least about 10%) of its active sulfur available for the electrochemical reaction. In many embodiments, the method will involve a step of forming a mixture in order to facilitate the formation of the electrode. A thin layer of such mixture is then deposited on a substrate and allowed to dry. In other modalities, no A mixture is formed and, instead, the step of homogenizing comprises homogenizing a solid phase mixture containing the active sulfur, the electron conductor, and the ion conductor. In some preferred embodiments, the resulting homogenous mixture is converted to an electrode by a process such as extrusion, scheduling, or a process analogous to conventional methods for processing solid state rubber, used in that art. In other preferred embodiments, the homogeneous mixture is deposited on a substrate by a process such as electrostatic deposition, cathodic deposition, vapor deposition, printing, transfer printing, lamination, or coating.

In preferred embodiments, the step of forming the sulfur-containing electrode -Mactivity involves a step of depositing a layer of the homogeneous mixture on a substrate by a technique that is not based on capillary action. If the homogeneous mixture is provided as a mixture, it is believed that such deposition without capillary action helps to ensure that the resulting film will not segregate and therefore will provide good contact between the active sulfur the ionic conductor and the electronic conductor, thus allowing a utilization greater than 5% of active sulfur. When a mixture is used to prepare the electrode, an additional drying step must be used to form the electrode. The mixture can be dried either on a non-adhesive substrate or on a current collector. In the later case, ^^ the electrode is completely manufactured, essentially, when drying. In the previous case, the dry electrode must first be removed from the non-adhesive substrate, and subsequently adhered to the current collector so that the electrode comprising active sulfur is in electrical contact with the current collector. These and other aspects of the invention will be described in detail and exemplified in the drawings and the detailed description below.

BRIEF DESCRIPTION OF THE DRAWINGS < Figure 1 provides a flow chart showing the main steps used to prepare an electrode according to this invention. Figure 2 illustrates a fixed tube apparatus for depositing a blend film on a substrate according to an embodiment of this invention. Figure 3 illustrates apparatus for continuous deposition of blend film according to one embodiment of this invention. Figure 4 provides a schematic of a Li cell / electrolyte separator / active sulfur electrode of this invention.

Fig. 5 illustrates the reversible cycling operation of a lithium cell and & g;, amorphous PEO / active sulfur) of this invention evaluated at 30 ° C for an active sulfur capacity of 330 mAh / g for each cycle. Figure 6 illustrates the availability of the active sulfur in the positive electrode of a lithium cell (Li / PEO amorphous / active sulfur) of this invention evaluated at 30 ° C. Figure 7 illustrates the availability of the active sulfur in the positive electrode of a lithium cell (Li / electrolyte separator in gel state / active sulfur) of this invention evaluated at 30 ° C. Figure 8 illustrates the availability of active sulfur at the positive electrode of a lithium cell (Li / PEO / active sulfur) of this invention evaluated at 90 ° C. .- ^ Figure 9 illustrates the reversible cycling operation of a lithium cell (Li / PEO / active sulfur) of this invention evaluated at 90 ° C at an active sulfur capacity of 400 mAh / g for each cycle. Figure 10 illustrates the reversible cycling operation of a lithium cell 5 (Li / PEO / active sulfur) of this invention evaluated at 90 ° C. Figure 11 illustrates the peak power performance of a lithium cell (Li / PEO / active sulfur) of this invention evaluated at 90 ° C. Figure 12a is a table illustrating the operation of cells prepared and operated as described in examples 1-8. table illustrating the operation of the cells prepared and operated as described in examples 9-15. Figure 13 illustrates the peak power operation of a lithium cell (Li PEO / active sulfur) of this invention evaluated at 90 ° C.

Best ways to effect the Invention Abbreviations aPEO amorphous polyethylene oxide (oxymethylene linked with polyoxyethylene) centimeter diethyl carbonate DMC dimethyl carbonate 5 DME dimethyl ether EC ethylene carbonate E.W. equivalent weight F.W. Weight formula GICs composed of graphite intercalation 0 g gram milliamper-hour millimeter MW molecular weight OCV open circuit voltage 5 PC propylene carbonate P.E.D. practical energy density PEO polyethylene oxide PEG polyethylene glycol PPP poly (p-phenylene) c 5si pounds per square inch PVDF polyvinylidene fluoride S sulfur T.E.D. theoretical energy density μA microamper 5 μm micrometer WE working electrode W / kg Watts per kilogram Wh / kg Watt-hours per kilogram W / l watts per liter ^^ ?. V weight volts Definitions "Metals" are defined here as being elements whose atoms commonly lose electrons during the formation of compounds. The phrase "alkali metals" is defined herein as the alkali metal family located in the LA Group of the periodic table, including lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs) ) and franc (Fr). The phrase "alkaline earth metal family" is defined herein as the HA Group of elements, including beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba) and radium (Ra). The phrase "transition metals" is defined here to include the following 5 metals: (1) the Scandium family: Scandium (Se), Yttrium (Y), Lanthanum (La) and the Lanthan series, and Actinium (Ac) ) and the series of actinides; (2) the titanium family: titanium (Ti), zirconium (Zr), and haf io (Hf); (3) the vanadium family: vanadium (V), niobium (Nb), and tantalum (Ta); cflF "(4) the chromium family: chromium (Cr), molybdenum (Mo), and tungsten (W) (5) the family of manganese, manganese (Mn), technetium (Te), and rhenium (Re); 6) the iron family: iron (Fe), cobalt (Co), and nickel (Ni); (7) the platinum family; ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir), and platinum (Pt); 5 (8) the copper family: copper (Cu), silver (Ag), and gold (Au); (9) the zinc family: zinc (Zn), cadmium (Cd), and mercury (Hg); (10) the aluminum family: aluminum (Al), gallium (Ga), indium (In), and thallium (TI); (11) the germanium family: germanium (Ge), tin (Sn), and lead (Pb).

The teimino "active sulfur" is defined here as the elemental sulfur or sulfur that would be elementary if the positive electrode were in its theoretical state of total charge. 5 The teimino "solid state" is defined here as being a material containing less than 20% by weight of a liquid. The term "gel state" is defined herein as being a material containing at least 20% by weight of a liquid wherein said liquid is immobilized by the presence of a gelling agent. 0 The term "component" is defined here as being (a) positive electrode, (b) , electrolyte separator, or (c) negative electrode.

Detailed description of the invention The present invention provides a positive electrode for battery systems in presentation of solid and liquid state, wherein the positive electrode is based on active sulfur which provides high power and specific energy, exceeding those of highly developed systems hitherto known and In use. Battery cell in ^ solid state display means that all the components of the battery are either solid or in a gel state. This also means that no component is in a liquid state. The equivalent weight of the active sulfur used in the redox reactions within the battery cells of this invention is 16 grams / equivalent (with a lithium metal as the negative electrode, the active sulfur in its theoretical total discharge state is Li2S ), leading to a theoretical specific energy of 2800 watt -5 hours per kilogram (Wh / kg) for a lithium cell that has an average OCV of 2.4 volts. So a high surplus specific energy is very unusual and highly attractive.

In addition, the batteries containing the positive electrode of this invention can operate at ambient temperatures. The battery systems of this invention energy at weight ratios beyond current demands for load leveling applications and / or electric vehicles, and can be manufactured with safety in units with reproducible operating values. This invention can be incorporated into a battery cell that includes solid state or gel state electrolyte separators. This method excludes the problem of a battery cell in liquid presentation that may suffer loss of electrolyte. For example, in lithium cells where a liquid electrolyte is used, the loss of electrolyte can leave lithium exposed to air, where it quickly reacts with water vapor. A substantive coating can prevent such ^ reactions and protect users and the environment from exposure to solvents but add undesirable weight to the battery. Using a presentation of solid state or gel state battery cells greatly reduces such problems of electrolyte loss 5 and lithium exposure, and can reduce the weight of the battery. Another embodiment refers to liquid presentation battery cells, which have a solid positive electrode based on active sulfur of this invention, and which have a solid negative electrode containing carbon (when in the condition or sodium and / or a mixture). carbon 0 ^ with lithium or sodium. Such a modality can overcome the problem of lithium depletion described in the prior art, for example, Rauh et al., Supra. In accordance with this invention, the positive compound electrode based on active sulfur and a battery system constructed with the positive electrode are provided.

The positive electrodes of this invention are preferably reversible, and the active metal-sulfur battery cells are preferably secondary batteries, and more preferably secondary thin film batteries. The invention relates in one aspect to the positive electrode of battery cells wherein both positive and negative electrodes are in solid state or gel state and The electrolyte separator is either a material in the solid state or a material in the tester state (see definition). In another aspect, as indicated above, the positive electrode of this invention is used in a battery cell containing a liquid electrolyte wherein the negative electrode is solid or in a gel state and contains carbon, carbon 5 inserted with lithium or sodium , or mixtures of carbon with lithium or sodium, However, whatever the presentation of the battery cells made with the positive electrodes of this invention, said positive electrode comprises elemental sulfur as the active component in the theoretical state of total charge. 0 The positive electrode * The active sulfur of the novel positive electrodes of this invention is preferably uniformly dispersed in a composite matrix, for example, the active sulfur can be mixed with a polymer electrolyte (ionically conductive), preferably a polyalkylene oxide, such as polyethylene oxide (PEO) in which an appropriate salt can be added, and an electronically conductive material. In addition, the ionically conductive material may be in the solid state or gel state presentation. In most cases it will be necessary or desirable to include appropriate, for the rapid transport of ion within the with electrodes based on intercalation materials. In addition, because active sulfur is not electrically conductive, it is important to disperse some amount of a conductive material electronically in the composite electrode. The preferred weight percentages of the main components of the 5 active sulfur-based positive electrodes of this invention in a theoretical total charge state are: from 20% to 80% active sulfur; from 15% to 75% of ionically conductive material (which may be in the solid state or in the gel state), such as PEO with salt, and from 5% to 40% of an electronically conductive material, such as carbon black, electronically conductive polymer, such as potyaniline.

Most preferably, those percentages are: from 30% to 75% of active sulfur; of 15% a "" 60% of the ionically conductive material; and from 10% to 30% of electronically conductive material. Even more preferable percentages are: from 40% to 60% of active sulfur; from 25% to 45% ionically conductive material; and from 15% to 25% of electronically conductive material. Another preferred percentage for the weight range for the electronically conductive material is from 16% to 24%.

Methods to make a positive electrode: ^ An important aspect of this invention is the ability to provide electrodes They have active material (commonly active sulfur and / or a polydisulfide polymer) in intimate contact with both an ion conductor and an electronic conductor. This facilitates the transport of the ion and the electron to and from the active material to allow approximately the use of the active material to be completed. For this purpose, the invention provides a method for producing electrodes which ensures that at least about 5% of the active material in the resulting electrode is available for the electrochemical reaction. None previous method produces ^ electrodes that have such high availability of active sulfur. ^^ A preferred method of making electrodes according to this invention is illustrated in the flow chart of Fig. 1. The method begins with a step 100 of combining the electrode components (including an electrochemically active material, an electronic conductor, and a ionic conductor). Then, in a step 102, the mixture is homogenized (and deagglomerated as required) so that the electrode components are well mixed and free of agglomerates. Typically, a mixture will be formed by the combination of the electrode components with a liquid in any of steps 100 or 102.

After the electrode components are hogenized and in the form of a gazelle, the mixture is placed on a substrate to form a thin film in a step 104. The best results will generally be obtained if the mixture is homogenized immediately before the formation of the movie in step 104. This ensures that the components of the mixture have not settled or separated to any significant degree, thus providing a uniform film with the desired electrode component ratio. Finally, in a step 106, the coated film is dried to form the electrode. The film preferably will thin enough to allow rapid drying so that the electrode components do not significantly 0 redistribute during drying step 106. The actual film thickness t depend, of course, the amount of liquid used in the mixture . The components that were combined in step 100 include at least one electrochemically active insulator (e.g., elemental sulfur or a polydisulfide). an electronically conductive material, and an ionically conductive material. The appropriate relationships of these materials are set forth above for the resulting electrodes. Generally, the same ratios can be used in the mixture used to make the electrodes. The electrochemically active insulator is preferably active sulfur, but any electrochemically active insulator or moderately conductive material can benefit from the inventive method. The ionic conductor is, as noted, preferably a polymeric ion conductor such as a polyalkylene oxide, and more preferably PEO or amorphous PEO. To increase the conductivity of the ion conductor, this typically be provided with a salt containing the transported ion (p. G., A lithium salt such as 5 trifíuorometanosulfanimida lithium or lithium perchlorate as described herein around the electrolyte ). The electronic conductor is preferably a carbon black polymer or an electronically conductive polymer such as polyaniline, polythiophene, polyacetylene, polypyrrole, etc. In an especially preferred embodiment, the Electrochemically active material is active sulfur, the ionic conductor is PEO "| Possibly with a small amount of an appropriate salt, and the electronic conductor is a carbon black In addition to the three aforementioned" necessary "electrode components other components can be added to the mixture including (1) materials to catalyze the transfer of electrons from the electronically conductive material to the active material, (2) additives to protect the surface of an active metal electrode (eg, the surfaces of sodium or lithium electrode) in cells employing such electrodes, (3) dispersants, (4) binders, and (5) surfactants. 0 The materials that catalyze the transport of electrons between the material Electrochemically active element and electronic conductor are known in the art and include, ™ for example, phthalocyanines, metallocenes, and bright yellow. Additives to protect a surface of an electrode active metal include, for example, organosulfur compounds such as poly-2,5-dimercapto-l, 3,4-thiadiazole, phosphates, iodides, iodine 5, metal sulfides, mtruros, and fluorides . It is considered that these materials provide a protective layer on the surface of the metal electrode. When casting into the active sulfur electrode (or other insulator), small amounts of these protectants will diffuse through the electrolyte to react with the metal electrode and irradiate the protective layer. In addition, a dispersant (or dispersants) such as Brij or > EG can also be added to the mix. Such materials reduce the tendency to agglomerate exposed by some of the necessary components such as carbon black. Agglomeration, of course, degrades the quality of the resulting electrode by preventing complete mixing of the components. Other additives are widely used to make positive electrodes and are known in the art to have various benefits. The use of such additives in the formation of electrodes is within the scope of this invention. As noted, the components of the electrode mixture will typically be dispersed in a mixture. Different liquids can be used in the mixture.

Typically, but not necessarily, the liquid will not dissolve the active sulfur or It can, however, dissolve polymer components such as PEO or a polymeric electronic conductor. Preferred liquids evaporate quickly so that the resulting film dries completely before you can the redistribution of the components occurs. Examples of acceptable liquids for the mixing system include water, acetonitrile, methanol, ethanol, tetrahydrofuran, etc.

Mixtures of liquid compounds can also be used. In continuous large-scale processes, it may be desired to use a relatively low volatility liquid such as water to facilitate recovery of the liquid for recycling. 0 The relative amounts of solid and liquid in the mixture will be governed by the # Viscosity required for subsequent processing. For example, electrodes formed by a tape casting apparatus may require a mixing viscosity different from that of electrodes formed with a Mayer rod. The viscosity of the mixture will, of course, be governed by factors such as the composition and amount of the components of the mixture, the temperature of the mixture, and the particle sizes in the mixture. When the mixture includes a soluble ionic conductor such as PEO, the mixing ratio is conventionally defined in terms of the amount of soluble material to liquid. The amounts of the remaining insoluble components are then fixed to the amount of soluble material. For electrodes containing PEO, Cß a preferred range of concentrations is between approximately 30 and 200 milliliters of solvent per gram of PEO. The exact arrangement in which the components are added to the mixture is not critical to the invention. In fact, as illustrated below in Examples 18 to 20, various methods have been found to work with this invention. In one mode, for example, soluble components such as PEO and Brij are first dissolved in the liquid solvent before the insoluble components are added. In another exemplary embodiment, all components except the crystalline PEO are dispersed and dissolved before the crystalline PEO is added. The Insoluble components can be added to the mixture sequentially or in a remixed IJB form (ie, the insoluble solids are mixed before being added to the mixture). The process of homogenizing the electrode components (step 102 of the figure 1) can take a variety of forms according to the current invention. The process can vary depending on whether the manufacture of the electrode is carried out intermittently or continuously. For small-scale intermittent operations, the appropriate mixing homogenization apparatus includes stir bars (preferably cross-type stir bars), paint mixers such as rotary blade mixers, or paint mixers, and shear mixers. k. In addition, any mixing apparatus conventionally used to make ^ "enamel baths" in the arts of ceramic processing will be sufficient for use with this invention. By way of example, some other batch mixing systems employ ball mills, drop mixing, shear mixing, etc. The amount of time required to obtain a conveniently homogeneous mixture can be determined by routine experimentation with each of these mixing equipment. The conveniently homogeneous mixtures are evidenced by the high _ availability of active electrode material in the resulting electrode. It has been found that with stirring rods, homogenization typically requires about 2 days, although with paint mixers and stirring or shaking mixers the homogenization requires less time (in the order of a few hours). In equalizing agitators for suspended solid particles, the torque per unit volume must generally remain constant. Even so, mixing times 5 are typically sigmficatively longer on large continents than on smaller ones and this should be factored at any higher scale. In large scale and / or continuous electrode manufacturing systems, an industrial agitator will generally be preferable. The design criteria for such Systems are well known in the art and are described in, for example, pages 222- ^ 64 McCabe and Smith "Unit Operations of Chemical Engineering" Third Edition. McGraw Hill Book Company, New York (1976) whose description is incorporated herein for reference purposes. Suitable systems include turbine agitators and radial and axial flow impellers in tanks or containers with round bottoms. In general, containers should not have corners or regions in which fluid streams can not easily penetrate. In addition, the system should be designed to prevent circulatory currents that entrain solid particles outside the container where they move downward and concentrate. Circulatory currents can be attenuated by using deflectors in the system (eg, vertical strips perpendicular to the vessel wall). Enclosed impellers and diffuser rings can also be used for this purpose. Immediately after the mixture has been homogenized, it is deposited as a film on a substrate (step 104 of Figure 1). The exact amount of time between homogenization and deposition will depend on the physical nature of the mixture (viscosity, solids concentration, particle size of solids, etc.). Separation and significant settlements of the solids in the mixture should be avoided. Settling it can be slowed by employing (a) small particles of low density solids, (b) high concentrations of solids, and / or (c) liquid highly viscous ^. In addition, the particles of the various solid components of the mixture can be chosen so that all of them are at the same speed, thus avoiding the problem of segregation. As far as possible, the mixture should be delivered to the substrate immediately after homogenization. It can be used, for example, conditioning ramp and supply systems such as those provided by EPH Associates, Inc. of Orem, Utah delivering the mixture to a homogenizer directly to the substrate. Preferably, the deposition step of the mixing film does not use centrifugal, capillary or other forces that tend to aggravate the separation of the solid components of the mixture. Thus, for example, procedures involving the removal of the substrate in the mixture will generally not be suitable for use in the present invention. According to this invention, preferred film-forming methods include: (1) deposition on a substrate by means of a fixed tube or structure by temporarily defining a chamber above the substrate, (2) spreading by means of a Mayer rod, and (3) ) spread by means of a scraper. Deposition via a fixed tube is illustrated in Figure 2 where a tube 122 is placed against a substrate 124 with sufficient force to prevent solids from the mixture from escaping out of the deposition region 120. The tube 122 preferably makes inert materials Ftal like glass tube. It should have a smooth bottom for good contact and a seal with the substrate 124 that is reasonably impenetrable. A sufficient amount of mixture is provided through the top of the tube 122 to cover the region 120. The mixing film can also be applied by spreading. In the intermittent process, a Mayer rod - which is about 1/2 to 1 inch (12.7 to 25.4 mm) in diameter wound with thin wires - may advantageously be used to transfer a thin layer of the mixed film onto the substrate. In continuous processes or by batch (intermittent), a Squeegee to provide a thin layer of mixture to a substrate sheet in motion, as explained in detail below. Still further, the mixing film can be applied by a lamination process, or by a printing process such as a screen printing process analogous to screen printing. Regardless of how the mixing film is applied, it should have a primary dimension, p. eg, the thickness, which allows a quick drying. This thickness, of course, will depend on factors such as the concentration of the mixture and the volatility of the liquid. In addition, the thickness of the mixing film should be chosen to produce electrodes of appropriate thickness for the final application of the battery. For example, low power, high energy applications, such as batteries for Pacemakers, can use thicker electrodes, for example, up to about ^ Knilimeters. In contrast, high-power applications, such as batteries for power tools or hybrid vehicles, should use thinner electrodes, e.g. eg, no greater than about 100 μm in thickness. It should be noted that 5 electrodes of appropriate thickness for low power applications can be made by laminating two or more thinner electrodes. In this way, the problem of slow drying associated with coarse electrodes can be avoided. Preferably the substrate on which the mixture is applied is a current collector such as a sheet of stainless steel, aluminum, copper, titanium, PET or metallized, or other conductive material which will not react under the conditions of • j? T operation of the cell. The appropriate current collectors can also take the form of expanded metals, screens, meshes, foams, etc. as it is known in art. In alternative embodiments, the substrate may be a sheet of inert material that does not adhere to the dry electrode material. One such suitable substrate material is Teflon®. After the electiode film has dried, it is detached from the substrate and then connected to a current collector such as one of the aforementioned materials. The connection to the current collector can be made by hot pressing, folding, etc. Alternatively, the current collector can directly on the electrode material by a technique such as spray Cathodic deposition, or another technique known to those of skill in art. The process of forming an electrode concludes with a drying step (step 106 of figure 1). In intermittent proce, these are preferably carried out in two steps: evaporation under ambient conditions for 30 seconds for 12 hours, followed by vacuum drying for approximately 4 to 24 hours at room temperature or at elevated temperature. In continuous proce, drying can be done by passing an electrode / substrate sheet through a drying chamber such as an IR dryer. A resulting typical active sulfur electrode layer will have a density of between about 0.001 6 and 0.012 grams per cm2.

A continuous process to prepare sheets of precipitated polymer will now be described above. The mixture is deposited on a moving sheet of substrette 222 that pa under the blade 226 to produce a thin mixture layer 230 homogeneously spread over the substrette 222. The lower tip of the blade 226 and the substrette 222 should be spaced apart from that. mixing layer 230 having a thickness that facilitates rapid drying as described above. The sub-step sheet 222 - which was moved along in the continuous process by a roll 232 - can be made from a variety of suitable materials including ~ ^ fe Flexible Teflon or any other release agent. In addition, the substiato can be a material that is destined to be incorporated in the electiodo finally produced.

For example, the substrate may include a metal foil, metallized PET, or screen that is to form a current collector at the final electiode. The sub-stack 222 with the mixture layer 230 is directed to a drying apparatus 248 operated at a temperature sufficient to remove much of the liquid from the mixture. This apparatus may include one or more dryers such as IR dryers, and may also have a condenser or other system (not shown) to recover the evaporated liquid from the mixture. If the substrate sheet 222 is not a current collector, it can be separated from either the electrode or the partially dried electiode after the substory entered the drying apparatus 248. The separation can then be performed by providing separate pick-up rails for sub-step 222 (outside drying apparatus 248) and for the resulting electrode sheet. Of course, if the substiato 222 is a current collector or is otherwise intended to be part of the electrode, no separation is required, and the substrate / electrode sheet is taken up on the spool 232 as shown. In alternative embodiments, the electrode is formed without first preparing a mixture. Rather the electrode components - including the insulator electrochemically active, the ion conductor, and the electron conductor - are homogenized in a solid state and formed into a sheet by extrusion or scheduling. The homogeneous solid-state mixture can also be laid on a sub-period by roll coating, knife coating, extrusion coating, curtain coating, or a related process. In each case, the mixture in the solid state is forced to flow by application of heat and / or pressure and the resulting viscous or viscoelastic mixture is passed through a die, a roller, or a blade. In such embodiments the PEO or other polymeric components should be present in appropriate concentrations to allow the formation of a viscous or viscoelastic material under the conditions found in the standard polymer apparatus. Details of the proper processing techniques of found in Middleman, "FUNDAMENTALS OF POLYMER PROCESSING", McGraw-Hill, Inc. 1977 which are incorporated herein by reference and for all purposes. In addition to these processing techniques involving flow, alternative techniques, within the scope of this invention, include electrostatic deposition as by processes analogous to xerography, cathodic deposition, vapor deposition, printing, laminating, and roller coating.

Additional dry processes conventionally used in the _ rubber processing to form electrodes according to this invention. Because each 0tT one of the above "dry" techniques does not involve a mixture, the drying step is not required. Thus, there is less opportunity for the solid components of the electrode to segregate or agglomerate after homogemization.

Electrolyte Separators and Liquid Electrolytes 5 The electrolyte separator for solid state display battery cells incorporating the positive electrode of this invention functions as a separator for positive and negative electrodes and as a transport medium for the metal ions. As defined above, the material for such M electrolyte separator is preferably electronically insulating, ionically conductive and electiochemically stable. When the battery cell is in a solid state presentation, all 5 components are either in the solid state or in the gel state and the separator in the liquid state. The aprotic organic liquids used in the electrolyte separators of this invention, as well as in the liquid electrolytes of this invention, are preferably of relatively low molecular weight, eg, less than 50,000 MW. Combinations of aprotic organic liquids can be used for "^^ electrolyte separators and liquid electrolytes of battery cells incorporating the positive electrode of this invention Preferred aprotic organic liquids of the battery cells incorporating the positive electrode of this invention include among other liquids related aprotic organic, sulfblan, dimethyl sulfone, dialkyl carbonates, tetianhydrofuran (THF), dioxolane, propylene carbonate (PC), ethylene carbonate (EC), dimethyl carbonate (DMC), butyrolactone, N-methylpyrrolidinone, tetiamethylurea, glymes, ethers, crown ethers, dimethoxyethane (DME), and combinations of such liquids. For battery cells, which incorporate the positive electrode of this invention, which contain a liquid electrolyte in which the negative electium contains carbon, said liquid is also an aprotic organic liquid as described above. Such a format also preferably contains a separator within the liquid electrolyte as discussed above. An exemplary solid state electrolyte separator combined with this invention is a ceramic electrolyte separator or a glass electrolyte separator that contains essentially no liquid. Polymeric electrolytes, porous membranes, or combinations of these are examples of the type of separator electrolyte to which an aprotic organic plasticizer liquid could be added in accordance with this invention for the formation of a solid state electrolyte separator containing less than 20% liquid. Preferably the electrolyte solid state separator is a solid ceramic or glass electyloid and / or solid polymer electyloid. The solid state ceramic electrolyte separator preferably comprises beta, Nasicon or Lisicon glass or ceramic type alumina material. The electylite solid state separator may include sodium alumina beta or any suitable polymeric electylite, such as polyethers, polyimines, polythioethers, polyphosphazenes, polymer blends, and the like, and mixtures and copolymers thereof in which it has been ~ ^^ optionally added an appropriate electylite salt. Preferred polyethers are polyalkylene oxides, more preferably, polyethylene oxide. Exemplary electolyte salts but optional for battery cells incorporating the positive electrode of this invention include, for example, trifluoromethanesulfanimide üthium (LiN (CF3802) 2), lithium triflate (LiCF3S03), lithium perchlorate (LiC104), LiPF6, LIBF4, LiAsF6, as well as, corresponding salts depending on the choice of the metal for the negative electrode, for example, co-deposited sodium salts, As indicated above the electrolyte salt is optional for the battery cells of this invention, in that upon discharge of the C > 5battery. the polysulfide or metal sulphides formed can act as electrolyte salts, for example M? ZS where x = 0 to 2 and z is the valence of the metal.

The negative electrode For the solid state battery cells incorporating the positive electrode of this invention, the negative electrode can comprise any metal, any mixture of metals, or any carbon or metal / carbon material capable of functioning as an active component of a negative electrode in combination with a positive electiodo of active sulfur. For example, any alkali metal or alkaline earth metal or transition metal can be used and particularly mixtures containing lithium and / or sodium. Preferred materials for the negative electiode for solid state battery cell presentations include sodium and / or lithium, and mixtures of sodium or lithium with one or more additional alkali metals and / or alkaline earth metals. Preferred materials for the negative electiode also include mixtures of sodium or lithium with one or more elements to form a binary or ternary alloy, such as, Na4Pb, lithium-silicon and lithium-aluminum alloys. 0 A particularly preferred metal for a negative electiode is sodium, or At least one sodium-based alloy (ie, at least 90% by weight of sodium) due to its low cost, low equivalent weight and its relatively low melting point of 97.8 ° C. However, other alkali metals such as Li or K, or mixtures thereof with Na, may also be used, as desired, to perfect the system as a whole. Also the preferred negative electrode materials for the solid state battery cells incorporating the positive electrode of this invention include carbon, carbon inserted with lithium or sodium and / or a mixture of carbon with sodium or lithium. Exemplary and preferred are the LiyC (where y = 0.3 to 2), such as, LiC6, the (^ * negative electrodes that comprise graphite or petroleum coke, for example, graphite intercalation compounds (GICs), and carbon embedded in highly disordered coals The inserted carbon can also be that in which some carbon has been alloyed with boron, or where the carbon has been prepared from low temperature pyrolysis (about 750 ° C), carbon or 5 polymers containing carbon-silicon so that the carbon product retains some hydrogen or silicon or both, (see Sato et al., "A Mechanism of Lithium Storage in Disordered Carbons," Science 264: 556 (22 April 1994), which discusses very good results with a preferred negative electrode of Li inserted into carbon based on poly p-phenylene (based on PPP).) For battery cells using the positive electrode of this invention that are in liquid presentation, the negative electrode it is carbon, carbon inserted with Htio or sodium, or mixtures of carbon and lithium or sodium as described above in relation to solid-state presentations, including preferable versions of carbon-containing electrodes. For any presentation, if the negative electrode contains only carbon, the cell is in the theoretical full discharge state, and the positive electiode comprises lithium or polysulfides or sodium sulfides. 0 The battery cells # The battery cells containing positive sulfur-based compound electrodes of this invention can be constructed according to conventional embodiments as described in the literature. For example, De Jonghe et al., U.S. Pat. No. 4,833,048 and Visco et al., U.S. Patent. No. 5,162, 175. It is understood that such conventional presentations are incorporated herein by reference. The novel battery cells embodying this invention, preferably secondary cells, more preferably thin-film secondary cells, can be constructed by any of the methods well known and conventional in the art.The negative electiode can be separated from the positive sulfur electrode, and both electrodes can be in physical contact with an ionically conductive electrolyte separator.The current collectors touch both positive and negative electrodes in a conventional manner and allow an electric current to be drained by an external circuit.Appropriate battery constructions can be made. according to the known art to assemble the cells and cell components as desired, and any of the Known configurations can be manufactured using the invention. The exact structures will depend primarily on the intended use of the battery unit. A general scheme for the novel battery cells of this invention in a solid state display can include a current collector in contact with the negative electiode and a current collector in contact with the positive electiode, and a state electrolyte separator. solid interspersed between the negative and positive electrodes. In a typical cell, all the components will be enclosed in an appropriate envelope, eg, plastic, with only the current collectors extending beyond the envelope. By this, the reactive elements, such as sodium or lithium in the negative electiode, as well as the other elements of the cell are protected. The current collectors may be sheets of conductive materials, such as aluminum or stainless steel, which remain substantially unchanged during discharge and cell charge, and which provide direct connections to the positive and negative electrodes of the cell. cell. The positive electrode film can be fixed to the current collector by direct casting in the current collector or by pressing the electrode film in the current collector. The positive electiode mixtures cast directly into current collectors preferably have good adhesion. The positive electrode films can also be cast (fi xed in expanded metal sheets) Alternatively, the metal lead wires can be fixed to the positive electiode film by airtight ripple, sprayed metal, cathodic deposition or other known techniques for Those skilled in the art.The positive sulfur-based electrode can be pressed together with the electrolyte separator sandwiched between the electrodes.In order to provide good electrical conductivity between the positive electiode and a metal vessel, an electronically conductive matrix of for example carbon or aluminum fibers or powders or metal mesh.

A particularly preferred battery cell comprises a solid sodium or lithium electrode, a polymer electrolyte separator, either in the solid state or in the gel state, preferably a polyalkylene oxide, such as polyethylene oxide, and a thin layer of positive compound electrode containing a 5 elemental sulfur electrode (which is in the theoretical state of total charge), and carbon black, dispersed in a polymer electrolyte. Optionally, the electrolyte separator in such a preferred battery cell may comprise an electrolyte salt.

Operating temperatures 10 j j »The operating temperature of the battery cells incorporating the novel positive electrode of this invention is preferably 180 ° C or lower. The preferred ranges of operating temperature depend on the application. Exemplary ranges of preferred operating temperature include from 40 ° C to 145 ° C; 5 from -20 ° C to 145 ° C; from -20 ° C to 120 ° C; and from 0 ° C to 90 ° C. More preferably for many applications, the cells embodying this invention operate at ambient temperatures or above ambient temperatures. Different embodiments of this invention can provide different ranges of preferred operating temperatures. The choice of the electolyte can influence the preferred operating temperature ranges for batteries incorporating the positive electiode of this invention, For example, when conventional PEO is used the preferred range is 60 ° C to 120 ° C; however when amorphous PEO (aPEO) is used, the battery can operate at room temperature, or in a range of 0 ° C to 60 ° C. 5 Gel presentations provide lower operating temperature ranges.

Exemplary battery cells using the positive electiode of this invention containing, for example, polymeric electyloid separator having an increasing percentage of an aprotic organic liquid immobilized by the presence of a gelling agent, can allow operating temperature ranges every time. An exemplary operating temperature range for a state battery The solid having gel state components of this invention would be from about -20 ° C to about 60 ° C. 5 A battery with a liquid separator and a negative electrode comprising carbon, inserted carbon and / or a mixture of carbon and lithium or sodium can operate in a preferred temperature range of -40 ° C to 60 ° C. The high range of operating temperature of the battery cells based on the positive electiode of this invention can be limited by the melting point of either a solid electrode or a solid electyloid. Thus negative sodium electrodes are limited to temperatures below 97.8 ° C, but sodium alloy electrodes, such as Na4Pb, can be used in a solid form above 100 ° C.

Specific energy and specific power The practical specific energies of the secondary cells used in this invention are preferably greater than 65 watt-hours per kilogram (Wh / kg), more preferably greater than 100 Wh / kg, still more preferably greater than 150.

^ Wh kg, even more preferably greater than 200 Wh / kg, and still further more preferably greater than 250 Wh / kg. While cells that have specific energies in the above ranges are preferred for many applications, these ranges should not be seen as limiting the invention. Indeed, it can be expected that the cells of this invention achieve specific energies superior to 850 Wh / kg. Thus, for some applications, a preferred practical specific energy range of the batteries embodying this invention is from about 100.

Wh / kg up to approximately 800 Wh / kg. The specific stable state practical powers of the secondary cells using this invention are preferably greater than 20 watts per kilogram (W / kg), more preferably greater than 50 W / kg, still more preferably? Higher than 100 W / kg, even more preferably higher than 150 W / kg, and still more preferably greater than 250 W / kg. It is anticipated that with the optimized battery construction for power, the steady state power of this invention may exceed 750 W / kg. A preferred practical practical energy range of the batteries embodying this invention is from about 90 W / kg to about 500 W / kg. Peak and pulse power performances would be many times greater than steady state power. Cells made with negative lithium electrodes, separators were constructed electolyte solid state or gel state, positive electiodes made with 3tt? elemental sulfur, polyethylene oxide (or modified polyethylene oxide) and carbon particles to test the operation of the batteries of this invention.

The examples of these tests will serve to further illustrate the invention but not to limit the scope of the invention in any way. 15 Example 1 Solid-state cell: cycling operation at an active sulfur capacity of 330 mAh / g for each rechargeable cycle evaluated at 30 ° C iß A positive electiode film was made by mixing 45% (percentage by weight) of elemental sulfur , 16% carbon black, amorphous polyethylene oxide (aPEO) and lithium trifluoromethanesulfanimide (where the concentration of electolyte salt to PEO monomer units (CH2CH 0) per salt molecule was 5 49: 1) , and 5% of 2,5-dimercapto-l, 3,4-dithiadiazole in an acetonitiyl solution (the ratio of solvent to PEO being 60: 1 by weight). The components were mixed by shaking for about two days until the mixture was well mixed and uniform. A thin film of positive electrode was cast directly into the stainless steel current collectors, and it was allowed that resulting from electiodo The polymeric electylite separator was made by mixing aPEO with lithium thiifluoromethanesulfanimide, (the concentration of electolyte salt being to units of PEO monomer (CH2CH20) per salt molecule of 39: 1) in an acetonitrile solution (the solvent ratio being polyethylene oxide of 15: 1 by weight ).

The components were mixed by agitation for two hours until the solution was uniform. Measured amounts of the separator mixture were poured into a retainer on a release film, and the solvent was allowed to evaporate to a - ^ ambient temperatures. The resulting electrolyte separator film weighed approximately 0.0144 gram per cm2. The positive electiode film and the polymer electrolyte separator were assembled under ambient conditions, and then dried under vacuum overnight to remove the moisture before being transferred to the argon receptacle for final assembly of the cell to a thickness of 3 mil (75 micron) lithium film (FMC / Lithco, 449 North Cox Road, Box 3925 Gastonia, NC 28054 (USA)). Schematic diagrams of the cell layers are shown in FIG. Once assembled, the cell was compressed at 2 psi and heated to 40 ° C for about 6 hours After heating the lithium layers, the electrolyte separator and the positive electrode were well adhered. then evaluated with a battery tester (Maccor SA., 2805 West 40th Strett, Tulsa, OK 74107 (USA)) in the receptacle at 30 ° C. That procedure was carried out to eliminate any problem of lithium contamination. The cell was cycled to a corresponding constant capacity to provide 330 mAh per gram of active sulfur in the positive electrode film. The values used were 100-20 μA / cm2 for the discharge and 50-10 μA / cm2 for the load at "• Cutting voltages of 1.8 and 3.0 volts respectively, Figure 5 shows the end of the discharge voltage of the cell after each recharge cycle As is evident from the diagram, the operation of the cell is very uniform.

Example 2 Solid-state cell: Total discharge capacity for 900 mAh / g of active sulfur evaluated at 30 ° C tafc A cell identical to that described in Example 1 was discharged at 1.8 volts at current densities of 100-20 μA / cm2 at 30 ° C to determine the total availability of the active sulfur in the film. The resulting discharge curve is seen in Figure 6. The total capacity of this film was above 900 mAh per gram of active sulfur, that is, a utilization of 54% of available active sulfur, where 100% would be 1675 mAh / gram.

Example 3 .ZA Solid state cell having components in the gel state: total discharge capacity for 900 mAh / gram of active sulfur evaluated at 30 ° C A positive electrode film similar to that described in Example 1 was made with a composition of 50% (percentage by weight) of elemental sulfur, 16% carbon black, an amorphous polyethylene oxide (aPEO) and trifluoromethanesulfonamide of htio ( at a concentration of 49: 1). The electyloid separator used was a gel made inside the receptacle to avoid contamination of oxygen and moisture. A starting solution consisting of 10% (weight percentage) of lithium trifluoromethanesulfanimide was made and 90% dimethylether of tetiaethylene glycol (tetraglima). Then a solvent of 90% of the starting solution. It was added to the % Kynar Flex 2801 (Elf Atochem of America, Inc., Fluoropolymers Department, 2000 Market Street, Philadelphia, PA 19103 (EUA)) ,. The mixture was stirred for a few minutes and then allowed to stand for 24 hours for the components to be absorbed into the Kynar. The mixture was stirred again for a few minutes to homogenize the components and then heated for 1 hour at 60 ° C. The electylite separator films were cast in a 0 release film, and the THF solvent was allowed to evaporate at room temperatures. j The resulting electrolyte separator film weighed approximately 0.0160 gram per cm. The resulting cell comprising the positive electrode film, the gel state electrolyte separator film, and the negative electiode of lithium was tested at the same conditions as those of the cell described in Example 2. The total capacity encased for this film it was also higher than 900 mAh per gram of active sulfur, that is, a utilization of 54% of available active sulfur, where 100% would be 1675 mAh / gram as shown in figure 7.

(^ Example 4 Solid-state cell: total discharge capacity for 1500 mAh / gram of sulfur evaluated at 90 ° C A positive electiode film similar to that described in Example 1 was made to be used above ambient temperatures with a composition of 50% (weight percentage) of elemental sulfur, 16% carbon black, polyethylene oxide (900,000 molecular weight) and lithium trifluoromethane-sulfonimide (at a concentration of 49: 1).

The solid state electyloid separator used was cast from a 900,000 MW PEO line in acetonitrile without additional electrolyte salts. The The resulting electrolyte separator film weighed approximately 0.0048 gram per cm2. The cell was assembled as described in Example 1. Once assembled, the cell was compressed at 2 psi and heated to 90 ° C for about 6 hours. The cell was tested at 90 ° C inside a convection oven located in the receptacle.

The cell was discharged at 1.8 V at values of 500 to 100 μA / cm2. The relative capacity for active sulfur versus 0 voltage during discharge is shown in Figure 8. The total capacity delivered by this film was also ESSf higher than 1500 mAh per gram of active sulfur, that is, a 90% utilization of the available active sulfur, where 100% would be 1675 mAh / g.

Example 5 5 Solid-state cell: cycling operation at a sulfur capacity of 400 mAh / g evaluated at 90 ° C A positive electiode film similar to that described in Example 4 was made With a composition of 50% (weight percentage) of elemental sulfur, 24% of black (^^ carbon, polyethylene oxide (900,000 molecular weight) and lithium trifluoromethanesulfanimide (a concentration of 49: 1). of electrolyte is the same as that described in Example 4. The cell was tested at 90 ° C and cycled to a corresponding constant capacity to deliver 400 mAh / g of active sulfur in the positive electrode film.The value used was 500 μA / cm2 for the 5 discharge and 1000 - 500 μA / cm2 for the load at cut-off voltages of 1.8 and 2.6 volts, respectively.

Figure 9 shows the end of the discharge voltage of the cell after each recharge cycle As is evident from the diagram, the cell operation is very uniform.

Example 6 Solid-state cell: cycling operation for each cycle for a cut-off voltage of 1.8 V evaluated at 90 ° C A positive electiode film identical to that described in Example 4 was made. The electrolyte separator is also the same as that described in Example 4. The cell was tested at 90 ° C and cycled between voltage limits between 1.8 - 2.6 volts. The values used were 500-100 μA / cm2 for loading. Figure 10 shows the capacity delivered after each recharge. As is evident from the diagram, most recharge cycles delivered up to 1000 mAh per gram of the active sulfur used in the cathode film.

Example 7 Solid state cell: peak power operation # evaluated at 90 ° C A positive electrode film similar to that described in Example 4 was made with a composition of 50% (weight percentage) of elemental sulfur, 16% carbon black, polyethylene oxide (900,000 molecular weight) and lithium trifluoromethanesulfamide. (with a concentration of 49: 1). The electyloid separator is also the same as that described in Example 4. The cell was tested at 90 ° C and discharged in pulses for a time of 30 seconds or at a cut-off voltage of 1.2 V. The discharge value ranged from 0.1 to 3.5. mA / cm2. The pulse power (W / kg) entangled by the cathode film versus the current density was shown in the Figure 11. As seen from the graph, a pulse power can be achieved Example 8 A cell was tested under the conditions described in Example 5 above, except that the cell was cycled to a constant capacity copespondent to deliver 200 mAh / g of the active sulfur in the positive electrode film. The electrode was prepared from 50% elemental sulfur, 16% carbon, and the PEO balance of 900,000 MW. A film of the electrode material was formed with a Mayer rod # in a current collector. The separator was as in Example 4 with 900,000 MW PEO and formed with a Mayer rod.

Example 9 A cell was tested under the conditions described in Example 5 above, except that the cell was cycled to a corresponding constant capacity to deliver 300 mA / g of the active sulfur in the positive electrode film. The electrode was prepared from 45% elemental sulfur, 16% carbon, 5% dimercapto-C ™, 3,4-dithiadiazole, and the PEO balance of 900,000 MW. A film of the electiode material was formed with a Mayer rod in a current collector. The separator was as in Example 4 with 900,000 MW PEO and formed with a Mayer rod.

Example 10. A cell was tested under the conditions described in Example 5 above, except that the cell was cycled at a constant capacity to deliver 400 mAh / g of the active sulfur in the positive electiode film. The electiode was prepared from 45% elemental sulfur, 16% carbon, 5% 2,5- ^ Eflimercapto-1,3,4-dithiadiazole, and the PEO balance of 900,000 MW. A film of the electrode material was formed with a Mayer rod in a current collector.

The separator was as in Example 4 with 900,000 MW PEO and was formed with a Mayer rod.

Example 11 A cell was tested under the conditions described in Example 5 above, except that the cell was cycled at a constant capacity to deliver 600 mAh g of the active sulfur in the positive electrode film. The electrode was • • Hf prepared from 50% elemental sulfur, 24% carbon, 1% PbS, and the PEO balance of 900,000 MW. A film of electrode material was directly cast in a current collector. The separator was as in Example 4 with PEO 15 of 900,000 MW and formed with a Mayer rod.

Example 12 A cell was tested under the conditions described in Example 6 above. The? 9 electrode was prepared from 50% elemental sulfur 16% carbon, and the PEO balance of 900,000 MW, A film of the electrode material was formed with a Mayer rod in a current collector. The separator was like that of Example 4 but with the addition of 1% PbS.

Example 13 A cell was tested under the conditions described in Example 6 above. The electrode was prepared from 50% elemental sulfur, 24% carbon, and the PEO balance of 900,000 MW and lithium trifluoromethanesulfanimide (at a - Efeeso ratio of 49: 1). A film of the electrode material was formed with a Mayer rod in a current collector. The separator was as in Example 4 with 900,000 MW PEO and formed with a Mayer rod. 5 Example 14 A cell was tested under the conditions described in Example 4 above but at 70 ° C. The electrode was prepared from 50% elemental sulfur, 24% carbon, and the PEO balance of 900,000 MW and hydrogen trifluoromethanesulfanimide (a ? ai a weight ratio of 49: 1). A film of the electiode material was formed with a Mayer rod in a current collector. The separator was like the one in Example 4 with PEO of 900,000 MW and formed with a Mayer rod.

Example 15 A cell was tested under the conditions described in Example 7, but with discharge values ranging from 0.4 to 9 mA / cm2. The electrode was prepared with ^ 50% elemental sulfur, 16% carbon, and the PEO balance of 900,000 MW. A film of the electrode material was formed with a Mayer rod in a current collector. The separator was as in Example 4 with 900,000 MW PEO and formed with a Mayer rod. As seen from the graph, an extraordinarily high pulse power of 7400 W / kg of the positive electrode can be achieved. Table 1 presented in Figure 12a summarizes the operation of the representative battery cells 5 of Examples 1-7 under the specific test conditions detailed in each example. Table 2 presented in Figure 12b summarizes the operation of the representative battery cells of examples 8-14 under the specific test conditions detailed in each example.

The specific energies and powers demonstrated and enumerated above are described in the whole compound positive electiode. The electolyte separators and the lithium sheets used for the laboratory tests were not perfected for the final battery. The battery projections are based on the use of polymeric electyloid separators of 5 μm thickness, 30 μm thick aluminum sheets and 2.5-5.0 μm thick current collectors. In addition, there is a 10% increase in weight intended for the external envelope assumed for batteries larger than 1 Ampere. Depending on the exact configuration and size of the laminar cell, the operation of the completed battery is approximately 30-70% of the performance of the positive electrode film. For simplicity, it has been used 50% for conversion between positive electiode operation and battery projections (this is equivalent to 100% of the battery charge). The calculated range of battery density ranged from 1.0 - 1.6 g / cm.3 depending on specific configurations and components. For simplicity, a density of 1.25 g / cm3 is used to calculate the projected energy density (Wh / 1). As is evident from the table, the battery systems containing the positive electrode of this invention demonstrate exceptionally high specific energies and ^^ exceed all solid state batteries based on intercalation compounds ^ hitherto known. Cells of this invention also overpass the performance of cells operating at higher temperatures such as the Na / beta cell "-alumina / Na2Sx (350 ° C), LiAl Li, the KCI / FeS2 cell (450 ° C) It is seen that the invention provides high energy and specific power cells, the operation of which exceeds that of highly developed systems now known and in use.At the same time, high power and energy are available at ambient temperatures or ambient operation .

Example 16 This example details a method for making active sulfur electrodes of this invention. Initially, a three-inch-long piece of stainless steel (Brown Metals) was cut from a four-inch-wide reel. Both sides of the sheet were then scraped with a scouring pad to remove any insulating coating and ensure better electrical contact between the film and the stainless steel current collector. The scraped stainless steel current collector was rubbed with acetone and Kimwipe EX-L until the Kimwipe was clean. A tongue was made to electrically connect the battery by cutting an outer section of the stainless steel. The resulting stainless steel current collector was then weighed. Then, the current collector was placed on a flat sheet of glass, and a standard 13 cm2 cast glass ring was placed on the center of a portion of the 3"X3" steel current collector. A syringe was then filled with a cathode mixture prepared according to one of the examples above.

Quickly 0.5 ml (or the desired volume to obtain the desired capacity per area) of the mixture was injected into the area inside the glass ring. Before he The solvent evaporated, the globule of the mixture was spread to cover the area inside the glass ring with a wet film of even thickness. Thereafter, the film was allowed to dry for several hours before removing the glass ring from the current collector. An X-acto knife was used to cut the film out of the glass ring. The current collector with the film was weighed again in order to obtain the weight of the cathode film. The electiodes were also prepared on Teledyne stainless steel or aluminum sheets as described above but without scraping the steel or aluminum as there are no insulating coatings as on Brown Metals steels.

Example 17 A stainless steel current collector was prepared as described in Example 15. The current collector was then placed on a flat and smooth glass sheet, and the middle part of the Mayer rod (# RDS 075 is now standard), It was centered on the edge of the current collector. Several milliliters of mixture (as many as necessary so that the mixture does not escape) were poured into the end of the rod. With one hand holding the substiato in position on the glass and the other holding the half of the rod, the rod was dragged through the current collector leaving a wet film. The film was then dried and the process repeated by the other end. The solvent content of the mixture was adjusted so that the wet film did not run (too solvent) and did not have a salient or raked appearance.

When the film was dried, it was placed on a glass ring (at the center of the 3"x 3" current collector), and a circular section was cut along the inner circumference of the ring. The excess film outside the circle was then scraped and the weight of the film detracted.

Example 18 ^ r Initially, an aluminum sheet current collector was prepared as in the Example 15 was placed on a sheet of glass, and the ends were punched so that it would not move while the Mayer rod moved. A Mayer rod was placed on one end of the current collector and sufficient mixture was injected to cover the desired area of current collector by means of a syringe on the front of the Mayer rod and on the current collector. When the movie was dry, the process was repeated as before but performed with a Mayer rod from a different end. When the film was dry, the undesirable film was scraped off, and the current collector was cut to the desired area.

Example 19 The following procedure was used to prepare a cathode mixture having 50% by weight of elemental sulfur, 16% by weight of acetylene black, 2% of Brij 35, and 32% by weight of PEO of 900,000 MW. A 38x38 mm cross shaker was placed in an 8 oz. Quorpac package (BWR Scientific, Brisbane, CA) with Teflon coating. To the bottle was added the following: 230 ml of acetonitiil (Aldrich grade HPLC), 6 g of sulfur powder sublimed and ground with balls (Aldrich), 1.93 g of acetylene (Shawinigin) carbon black (Chevron Cedar 0 Bayou Plant) , and 0.24 g of Brij 35 (Fluka). The contents of the bottle were then stirred overnight on a magnetic stir plate. The power of the plate of stirring was adjusted to stir at as high RPM as possible without splashing or sucking air. The next day, because the mixture was rapidly stirred, 3.85 g of 900,000 MW PEO (Aldrich) was added in a stream so that no large lumps of PEO flammable solvents were formed, but many tiny PEO solvents were formed. inflamed During the next two days, the speed of the stirring bar was adjusted to keep the RPM as high as possible, again without splashing or sucking air. After stirring for two nights, the PEO dissolved and the mixture was used to prepare thin films for either the cast ring technique or the Mayer rod technique, alternatively, sublimated and precipitated sulfur were used instead of ground sulfur. with balls described above, but instead of mixing for two nights, approximately two weeks of agitation were required.If the mixture is mifor only two nights the resulting thin film was found to be porous and lumpy.

The following procedure was used to prepare a cathode mixture 50% by weight of elemental sulfur, 24% by weight of acetylene black, 2% in weight of Brij 35, and the balance PEO of 900,000 MW: trifluoromethanesulfanimide of Mo (20: 1) in acetonitrile (my AN: gram PEO, 90: 1). A 38 x 38 mm cross shaker 5 was placed in an 8 oz container. Quorpac (BWR Scientific, Brisbane, CA) with a Teflon coating. The following was added to the filler: 0.59 g of lithium thifluoromethanesulfanimide (added in a dry box), 200 ml of acetonitrile (Aldrich grade HPLC), 5 g of sublimed sulfur and ground with balls (Aldrich), 2.4 g of acetylene (Shawinigin) ) carbon black, (Chevron Cedar Bayou Plant), and 0.2 g of Brij 35 (Fluka). Afterwards, the contents of the container were stirred overnight on a J magnetic stirring plate. The power of the stir plate was adjusted to adjust the stirring at as high RPM as possible without splashing or sucking air. The next day, because the mixture was rapidly stirred, 1.8 g of 900,000 MW PEO (Aldrich) was added in a stream so as not to form a few large tepes of inflamed PEO solvents, but preferably many tiny tepones of PEO solvents that are inflamed. During the next two days, the speed of the stirring bar was adjusted to keep the rpm as high as possible, again without splashing or sucking air. After shaking for two nights, the ^^ PEO was dissolved and the mixture was used to prepare thin films by techniques of o ^ Mayer rod or cast ring.

Example 21 The following procedure was used for various compositions of mix (identified later). First, a glass container and a stir bar were washed with acetone, and the stir bar was placed in the jar. Then an appropriate amount of acetonitrile (depending on the subsequent process) was added to the jar and the container was covered. The container with its contents was placed in a stirring plate operated at sufficient power to create a vortex in the icetonitrile. Then, the PEO was measured and slowly added to the package while it was still on the stir plate. The PEO was introduced in very small quantities to maximize contact with acetonitrile and promote rapid mixing. If the salt was added, it was measured and added as the PEO. If there were other solubles (Brij) to be added, they were also mixed at this point. All the components were mixed until dissolved. Then, all the insoluble materials including sulfur and carbon were measured and added to the mixture. The mixed 0 was carried out for a minimum of two days. The mix combinations JA used were as indicated below: (A) 50% by weight of elemental sulfur; 24% Carbon (Acetylene Black); 2% Brij 35; 24% of (20 moles of 900K PEO for 1 mole of trifluoromethanesulfanimide of thio) with 90 ml of acetonitrile per gram of PEO. 5 (B) 50% by weight of elemental sulfur; 16% Carbon (Acetylene Black); 1% Brij 35; 33% PEO of 900K with 60 ml acrylonitrile per gram of PEO. The ranges of components used to prepare various compositions according to this example are as follows: 24% -55% by weight of sulfur _ «Elemental 8% -24% by weight of Carbon (Acetylene Black); 30 ml of acrylonitrile per 0 ^ gram of PEO to 110 ml of acetonitrile per gram of PEO; and 40, 60, and 90 mi water per gram of PEO. Other compositions having various additives fixed to elemental sulfur according to the following. (1) 5% by weight of Brillant Yellow Dye additive with 55% elemental sulfur; (2) 5% 2,5-dimercapto 1,3,4-dithiadiazole with 45% elemental sulfur; (3) 2% by weight of thious iodide with 48% of elemental sulfur, (4) 5% by weight of iodine with 50% of sulfur; (5) 1% by weight of PbS with 49% elemental sulfur; and (6) 5% by weight polyethylene dithiol with 45% elemental sulfur. The foregoing describes the present invention and its currently preferred embodiments. The various variations and modifications in the practice of this invention it is expected to occur to those skilled in the art. Such modifications and jfe > Ariations are included within the following claims. All references cited herein are incorporated by reference.

Claims (47)

1. A positive electrode comprising a mixture of a) active sulfur; b) an electronic conductor mixed with the active sulfur so that the electrons can move between the active sulfur and the electronic conductor; and c) an ionic conductor blended with the active sulfur so that the ions can move between the ionic conductor and the active sulfur, wherein the mixture has about 10% and about 100% active sulfur available for the electrochemical reaction.

2. The positive electrode of claim 1, further characterized in that the > The mixture is electrically connected to the current collector.

3. The positive electiode of claim 1, further characterized in that the electiode is operated at about -40 ° C and about 180 ° C.

4. The positive electiode of claim 1, further characterized in that the mixture contains, between about 20% by weight and approximately 80% by weight of active sulfur

5. The positive electrode of claim 4, further characterized in that the mixture contains, from about 40% by weight to about 60% by weight of active sulfur.

6. The positive electiode of claim 1, further characterized in that the electronic conductor is selected from the group consisting essentially of carbon black, compounds with carbon-carbon or carbon-nitrogen double bond conjugate, electronically conductive polymers, polyaniline compounds, polythiophene compounds, polyacetylene compounds, polypyrrole compounds, and 5 combinations of these

7. The positive electiode of the claim 1, further characterized in that the mixture contains, between about 5% by weight to about 40% by weight of electronic conductor.

8. The positive electiode of claim 1, further characterized in that the Jjénezcla contains, from about 8% by weight to about 24% by weight of the electronic conductor.

9. The positive electrode of claim 1, further characterized in that the ion conductor is a solid or a gel.

The positive electrode of claim 9, further characterized in that the ion conductor is selected from the group consisting essentially of polymer electrolytes, ceramic electrolytes, glass electrolytes, beta alumina compounds, and combinations thereof.

11. The positive electrode of claim 9, further characterized in that the The ionic conductor comprises an electylite salt which complexes with the compounds selected from the group consisting essentially of polyether compounds, polyimine compounds, polythioether compounds, polyphosphazene compounds, polyalkylene oxide compounds, 15 polyethylene, and amorphous polyethylene oxide compounds, and combinations thereof.

12. The positive electiode of claim 11, further characterized in that the solid state ionic conductor further comprises between about 0.1% and about 20% aprotic organic liquid.

The positive electrode of claim 12, further characterized in that the aprotic organic liquid is selected from the group consisting essentially of sulfolan compounds, dimethyl sulfone compounds, tetrahydrofuran compounds, propylene carbonate compounds, dialkyl carbonate compounds, ethylene carbonate compounds, dimethyl carbonate compounds, butyrolactone compounds, N-methylpyrrolidinone compounds, tetramethylurea compounds, dioxylan compounds, glyme compounds, ether compounds, crown ether compounds , dimethoxyethane compounds, and combinations of these.

14. The positive electiode of claim 9, further characterized in that the ionic derivative is a gel including a gelling agent selected from the group consisting essentially of polyvinylidene fluoride compounds, hexafluoropropylene-vinylidene fluoride copolymers, polyacrylonitrile compounds, crosslinked polyether compounds , polyalkylene oxide compounds, polyethylene oxide compounds. and combinations of these.

15. The positive electrode of claim 1, further characterized in that the mixture further comprises one or more of the following: binders, electiocatalysts, surfactants, dispersants, and coating-forming additives 10 protective. ^^ i

16. The positive electrode of claim 1, further characterized in that the mixture is in the solid or a gel.

17. A battery cell characterized in that it comprises: a) a positive electrode comprising a mixture of i) between about 20% a 15 about 80% active sulfur in percent by weight; ii) an ion conductor in a gel or solid state in percent by weight between about 15% to 75%; and iii) an electronic conductor in a percent by weight of about 5% and about 40%; b) a current collector electrically connected to the ^ - positive electrode; c) a negative electrode; and d) an electyloid separator; where The mixture has about 10% and about 100% of the active sulfur available for the electrochemical reaction.

18. The battery cell of claim 17, further characterized in that the electrolyte separator is a solid state electyloid separator.

19. The battery cell of claim 17, further characterized in that the electylite separator is an electrolyte separator in a gel state.

20. The battery cell of claim 17, further characterized in that the electyloid separator is a liquid electrolyte separator.

21. The battery cell of claim 17, further characterized in that the faithful negative electrode is a negative electrode in the solid state.

22. The battery cell of claim 17, further characterized in that the negative electrode is a negative electrode in the gel state.

23. The battery cell of claim 17, further characterized in that the negative electrode is a liquid negative electrode.

24. A battery cell characterized in that it comprises: (a) a positive composite electrode comprising active sulfur in a weight percentage of 20% to 80%, an ion conductor in a weight percentage of 15% to 75%, and a conductor 10 electronic in a percentage by weight of 5% to 40%; (b) a negative electrode; and (c) an electylite separator in the solid state or an electiohte separator in the gel state; wherein the positive electiode has between about 10% and about 100% of the active sulfur available for the electrochemical reaction.

25. A battery cell according to claim 24, further characterized in that the negative electrode is selected from the group consisting of alkali metals, alkaline earth metals, transition metals, mixtures of alkali metals, alkaline metals and transition metals, carbon, carbon inserted with sodium or sodium, and mixtures of carbon with lithium or sodium.

A battery cell according to claim 25, further characterized 2? ™ ^ because the negative electrode is selected from the group consisting essentially of lithium, sodium, a mixture of carbon with lithium or sodium, or carbon inserted with lithium or sodium.

27. A battery cell according to claim 25, further characterized in that the negative electiode is selected from the group consisting essentially of 25 hr, sodium, Na4Pb, lithium-silicon alloys and lithium-aluminum.

28. A battery cell according to claim 24, further characterized in that the electrolyte separator is in the gel state.

29. A battery cell according to claim 24, further characterized in that the electrolyte separator is in the solid state.

30. A battery cell characterized in that it comprises: (a) a negative electrode comprising carbon, carbon inserted with lithium or sodium, or a mixture of 5 carbon with lithium or sodium; and (b) a compound positive electiode comprising active sulfur in a weight percentage of 20% to 80%, an ion conductor in a weight percentage of 15% to 75%, and an electronic conductor in a weight percentage of 5%. % to 40%; wherein the positive electrode has between about 10% and about 100% of the active sulfur available for the electrochemical reaction. 0

31. A battery cell according to claim 30, further characterized by ^ because it also comprises an electolyte salt in a liquid electrolyte.

32. A battery cell according to claim 31, further characterized in that it further comprises a dentio separator of the liquid electyloid.

33. A battery cell according to claim 30, further characterized in that the negative electrode comprises lithium inserted into highly disordered coals, graphite intercalation compounds or Li? C6 where y = 0.3 to 2.

34. A method for forming an electiode containing active sulfur, characterized in that the method comprises the following steps: combining sulfur ^ _ ^ active, an electronic conductor, and an ionic conductor to form a mixture; Ó ^ ^ homogenize the mixture to form a homogeneous mixture; and forming the electiode containing active sulfur from the homogeneous mixture, wherein the electiode containing active sulfur has at least about 10% of its active sulfur available for the electiochemical reaction.

35. The method of claim 34, further characterized in that method 5 includes a step of forming a mixture by combining the active sulfur, the electronic conductor, and the ionic conductor with a liquid.

36. The method of claim 33, further characterized in that the JjÉfe mixture forms from a dispersant in addition to the active sulfur, the electron conductor, the ion conductor, and the liquid.

37. The method of claim 35, further characterized in that the step of homogenizing involves de-agglomerating the mixture to form the homogenous mixture.

38. The method of claim 37, further characterized in that the step of forming the electiode containing active sulfur includes a step of applying a mixture layer of the homogeneous mixture to a substi- tiate.

39. The method of claim 38, further characterized in that the mixing layer is formed in a current collector. J

40. The method of claim 38, further characterized in that the mixing layer is formed in a non-adhesive substrette.

41. The method of claim 40, further characterized in that it further comprises the following steps: drying the mixture layer to form the electiode 15 containing active sulfur; remove the electrode containing active sulfur from the non-adhesive substrate; and adhering the electrode containing active sulfur to the current collector so that the electiode containing active sulfur is in electrical contact with the current collector. ^

42. The method of claim 38, further characterized in that further 0 ^ comprises a step of drying the mixture layer to form the electiode containing active sulfur.

43. The method of claim 38, further characterized in that the mixing layer is continuously formed in the substrate which is in permanent contact with a mixing source.

44. The method of claim 34, further characterized in that the step of homogenizing comprises homogenizing a solid phase mixture containing the active sulfur, the electron conductor, and the ion conductor.

45. The method of claim 34, further characterized in that the electonic driver employed in the combining step is selected from the group consisting of carbon and conductive polymers.

46. The method of claim 34, further characterized in that the ion conductor is a polyalkylene oxide.

47. The method of claim 34, further characterized in that it further comprises a step of preparing an electiochemical cell containing the electrode containing active sulfur. 10 * fifteen > ^ 5 0 VMRA (PCT1267) 07/96